But the busting of a boom is not always the end of the story. Weak players will go under, as companies like Pets.com did during the Internet bust. But for stronger companies -- and Facebook is the strongest social player out there -- value will be found, at some price, by someone.

As of Monday's close, Facebook was valued at about $42 billion. It should get even cheaper today, as investors digest how early investors like Peter Thiel are cashing out, as reported at Business Week.

By November more than 1.7 billion new shares will have been unlocked and become tradeable. Many of those shares, like Thiel's, will have been obtained at pennies per share, or will have been grants to early employees. With no real basis in a stock with an iffy future, selling pressure will continue through the end of the year.

Still, there is value here. Take a look at Facebook's balance sheet and you will see $10.1 billion in cash and short-term investments, as of June 30. The company booked $1.184 billion in revenue for that quarter. It had a huge run-up in administrative costs during that time, causing a loss, mostly related to going public, but it also had a huge increase in research investment during that same quarter, which is a good thing.

Michael Miller, a long-time PC Magazine editor whom I trust, noted in May that Facebook has built three big data centers on which it spent more than $860 million during the previous year. (See his article at PC Magazine.

Facebook is using an open architecture for both hardware and software and is focused on managing its infrastructure at the lowest possible cost.

If Facebook can return to the 20% after-tax margins it enjoyed in its March quarter, before the IPO, and stabilize, you're looking at a company with annual sales of $5 billion, profits of $1 billion and real opportunities for continued growth.